<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        #result{
            width: 200px;
            height: 100px;
            border: solid 1px #903;
        }
    </style>
</head>
<body>
    <div id="result"></div>
    <script>
        const result = document.querySelector('#result')
        result.addEventListener('mouseover',function(){
            // 1.创建对象
            const xhr = new XMLHttpRequest()
            // 2.初始化 设置请求类型与url
            xhr.open('POST','http://127.0.0.1:8000/server')
            // 设置请求头
            xhr.setRequestHeader('Content-Type','application/x-www-form-urlencoded')
            xhr.setRequestHeader('name','atguigu')
            // 3.发送,post请求可以传递参数
            // xhr.send('a=100&b=200&c=300')
            // xhr.send('a:100&b:200&c:300')
            xhr.send('12332112312')


            // 4.事件绑定
            xhr.onreadystatechange = function(){
                if(xhr.readyState === 4){
                    if(xhr.status>=200&&xhr.status<300){
                        // 处理服务端返回的结果
                        result.innerHTML = xhr.response
                    }
                }
            }
                        
        })
    </script>
</body>
</html>